Polymer nonlinear optical materials have been studied at length, especially their use in connection with second order nonlinear optical processes. Typical materials of interest include polymers with an acrylate backbone and sidechain chromophores of the congregated aromatic class for example, as are taught in U.S. Pat. Nos.: 5,044,725; 4,822,865; and 4,801,670. Such polymers may be incorporated into high speed waveguiding modulators, for example, as shown by Teng applied physics letters 60 (13), Mar. 30, 1992, or in parametric devices including frequency doublers as disclosed in U.S. Pat. Nos.: 4,865,406; 4,971,416 and 5,061,028. Generally speaking, nonlinear optical polymer material is poled in an electrical field when used in a second order nonlinear optical device so that the required non-centrosymmetric molecular orientation is achieved. Poling maybe accomplished by a variety of methods, for example, by applying an electric field to a film between electrodes at elevated temperatures or by way of corona poling as reported by Mortazayi et al. Journal of the Optical Society Am.B/Vol. 6, No. 4/April, 1989, pp. 733-741. Typically, poled films of the foregoing class exhibit a positive .beta. value; however, some material such as the quinodimethane compounds exhibit negative .beta. values. See e.g. U.S. Pat. Nos.: 4,783,151 and 4,719,281. Of particular interest to the present invention is harmonic processes in polymer nonlinear optical materials. In this respect, pertinent literature includes: Nazarathy M. et al. "SPREAD-SPECTRUM NONLINEAR-OPTICAL INTERACTIONS QUASI-PHASE MATCHING WITH PSEUDORANDOM POLARITY REVERSALS", Optics Letters Vol 12,. No. 10, p. 823 et seq. October, 1987; Singer K. D. et. al. "SECOND HARMONIC GENERATION IN POLED POLYMERS FILMS" Applied Physics Letters, 49 (5), p. 248 et seq. Aug. 4, 1986; Azumai, Y. et al., "EFFICIENT SECOND-HARMONIC GENERATION WITH A SLAB WAVEGUIDE COMPOSED OF PERIODICALLY CORONA-POLED ORGANIC COPOLYMER", Japan Journal of Applied Physics, Vol. 31, (1992)pp. 1358-1364, Part I, No. 5A, May 1992; Magel, G. A. et al., "QUASI-PHASE-MATCHED SECOND-HARMONIC GENERATION OF BLUE LIGHT IN PERIODICALLY POLED LiNbO.sub.3, Applied Physics Letters, 56 (2), Jan. 8, 1990, pp. 108-110; Mortazayi, M. A. et al., "HARMONIC GENERATION WITH ULTRASHORT PULSES USING NONLINEAR POLED POLYMERIC THIN FILMS", Applied Optics, Vol. 28, No. 15, Aug. 15, 1989, pp. 3278-3280; Khanarian. G. et al., "QUASI-PHASE-MATCHED FREQUENCY DOUBLING OVER 5 mm IN PERIODICALLY POLED POLYMER WAVEGUIDE", Electronics Letters 26, pp. 2105 et seq., 1990; Bierlein , J. D. et al., "BALANCED PHASE MATCHING IN SEGMENTED KTiOPO.sub.4 WAVEGUIDES", Applied Physics Letters 56 (18), Apr. 30, 1990, pp. 1725-1727 and Jerphagnon J. et al., "MAKER FRINGES: A DETAILED COMPARISON OF THEORY AND EXPERIMENT FOR ISOTROPIC AND UNIAXIAL CRYSTALS", Journal of Applied Physics, Vol 41, No. 4, Mar. 15, 1970, pp. 1667-1681.
Polymeric films offer processing advantages and indeed increased fabrication options over inorganic materials. Such polymers have been used for example, to fabricate a copolymeric nonlinear optical media having a crystallographic molecular alignment in the film plane and a net dipolar molecular orientation normal to the film plane as and would be useful, for example, in a spatial light modulator. See U.S. Pat. No.: 4,957,655 to Khanarian et al. likewise, poled polymer films have been laminated to polyimide films and used as patch sensors to test integrated circuit substrates. See, e.g. Nagatsuma, T. et al. "ORGANIC PATCH SENSOR FOR ELECTRO-OPTIC MEASUREMENT OF ELECTRICAL SIGNALS AND INTEGRATED CIRCUITS", Electronics Letters, 27, 1932 (1991). So also, Shocraw et al. report on recent experiments which measure the effects of the photo-induced generation and transport of charge on the refractive index of polymeric films having a second order nonlinear response period. Two approaches were taken to observe such effects. In the first, the photoconductor and light refractive processes were separated by confining these functions to separate layers in a multi-layer structure. In the second, photo conduction and refractive functions were combined in the same layer. The modulation of the refractive index was then measured in response to photo conduction. Proceedings SPIE-International Society of Optical Engineering (U.S.A., Vol. 626, 1992) pp. 2-8.